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An 82 g arrow is fired from a bow whose string exerts an average force of 95 n on the arrow over a distance of 77 cm. what is the speed of the arrow as it leaves the bow?

User Paul Rad
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1 Answer

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You need to find speed, v.
And you (should) recognize the famous F=ma.

We've got data for F and m, so we can find a first!

a = (f)/(m)
a = 95N / 0.082 kg


Now from a we nees to find v. But how is v and a related?

a = v * (dv)/(dx)
where dv is the change in speed (some unknown v minus zero since arrow is initially at rest). dx is the distance where the arrow experiences a force (77 cm!).

Now you know values for a, dv, and dx... you can plug those in and find v!



User Hansen
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